exterminate (v.)

word-forming element, in English meaning usually "out of, from," but also "upwards, completely, deprive of, without," and "former;" from Latin ex "out of, from within; from which time, since; according to; in regard to," from PIE *eghs "out" (source also of Gaulish ex-, Old Irish ess-, Old Church Slavonic izu, Russian iz). In some cases also from Greek cognate ex, ek. PIE *eghs had comparative form *eks-tero and superlative *eks-t(e)r-emo-. Often reduced to e- before -b-, -d-, -g-, consonantal -i-, -l-, -m-, -n-, -v- (as in elude, emerge, evaporate, etc.).

1550s, "goal, end, final point," from Latin terminus (plural termini) "an end, a limit, boundary line," from PIE *ter-men- "peg, post," from root *ter-, base of words meaning "peg, post; boundary, marker, goal" (source also of Sanskrit tarati "passes over, crosses over," tarantah "sea;" Hittite tarma- "peg, nail," tarmaizzi "he limits;" Greek terma "boundary, end-point, limit," termon "border;" Gothic þairh, Old English þurh "through;" Old English þyrel "hole;" Old Norse þrömr "edge, chip, splinter"). "The Hittite noun and the usage in Latin suggest that the PIE word denoted a concrete object which came to refer to a boundary-stone." [de Vaan]

In ancient Rome, Terminus was the name of the deity who presided over boundaries and landmarks, focus of the important Roman festival of Terminalia (held Feb. 23, the end of the old Roman year). The meaning "either end of a transportation line" is first recorded 1836.

c. 1400, "an angel who expels (people from a country)," from Late Latin exterminator, from past-participle stem of Latin exterminare  "drive out, expel, put aside, drive beyond boundaries," also, in Late Latin "destroy" (see exterminate). As a substance for ridding a place of rats, etc., by 1848; as a person whose job it is to do this, by 1938. Old English glossed Latin exterminator with ofdræfere ("off-driver").